AbdulAlhazred
Legend
One epic daily, engagement is no longer the Dragon's choice. I made this point. If you assume a mortal population and epic creatures, then among the mortal population there are going to be epic characters. These have Don't Need to Hit effects like prone/dominate/etc and the ability to rapidly travel from place to place via portals or what have you, then 1,000 peasant archers and one of the mortal epic people who guard/rule/run the kingdom can take out any epic level monster. Since they can do so in two rounds the equation comes down to one daily from a mortal epic NPC = one dead epic creature that was attacking the town.
Not sure what the rules say on ranges, but flame simply doesn't travel that far. 500 feet is an enormous distance for flame to travel from a single source, being pushed only by the sheer breath-force of the dragon.
Why would the dragon come within a MILE of said militia? What purpose would it serve? The military situation is a militia that can march at say 10 miles a day, or maybe if you have a REALLY well trained force they might even make 40 miles on a good day, tops. OTOH you have a dragon that flies at basically 3x their speed. They can sit on top of exactly one target and guard it, until the food runs out. The dragon can just go around the countryside burning and pillaging, driving all the refugees in to help eat the army's food and making sure that everyone will starve. Then it goes home or gnaws on whatever it finds elsewhere until said militia inevitably disbands.
There is no physical danger to the dragon at all. The situation is fundamentally asymmetric. The peasants MIGHT arguably have a firepower advantage, but they have a zone of control that is very limited, 1/3 the speed of their adversary, and in any group smaller than say 500 are basically going to die horribly.
Yes, if there are epic PCs around then the EPIC dragon has a problem and the militia might be a useful resource for them in some fashion. PCs at that level have equivalent mobility and firepower. It is probably inevitable that there will be a meeting, but again the dragon really has no motive to go near the militia, not even miles near. The PCs can try to pull some ruse or whatever and make it happen (sounds fun) but left to its own devices the dragon will probably just guard its treasure and assume that the annoying humans will go away in a couple years. Or send its minions etc out to deal with them.
Anyway, the whole question was "do towns full of human militia keep epic threats in check". I think the answer is maybe kind of. They might work reasonably well on some threats and not at all on others. There are certainly MANY epic threats that it is hard to see being thwarted by JUST ordinary mostly level 1 minion kind of people.
And I don't think personally that 1:1000 humans are epic, nor 1:10000, nor even 1:1 million. My idea of epic is pretty much "you are it". Maybe in the world you will find a small number of other scattered figures of great power, but the PCs are the Jason or Hercules or Merlin of their age. Not every town and city (or even kingdom) can count on calling one out at need. OTOH the gods/fates/whatever tend to see to it that some show up at the very most critical time and place in history. Its sorta like Elan's Dad said in the last couple OotS, inevitable dramatic structure.